A server such as a web server and a mail server receives a request and the like for acquiring a mail from a plurality of communication destinations (communication devices) via a communication network such as an intranet or the Internet.
For example, Patent Literature 1 and Patent Literature 2 disclose devices that manage a server capable of processing a request signal received via a communication network, respectively. The technologies disclosed in Patent Literature 1 and Patent Literature 2 will be respectively described.
The managing device disclosed in Patent Literature 1 generates a request category log in which the number of request signals received via the communication network are classified based on predetermined time intervals and types of the requests. The managing device further generates, in accordance with predetermined time interval, a system log in which a resource usage amount in the server managing the requests are recorded. The managing device calculates a usage amount of resources required for processing the requests every request on the basis of the generated request category log and the generated system log.
The request limiting device disclosed in Patent Literature 2 can limit a request having high possibility of reducing processing loads according to the state of the loads in the server. The request limiting device classifies requests into a plurality of request patterns, and calculates loads when performing request-based processing every classified request pattern. For a certain request, the request limiting device specifies a request pattern to which the request belongs, and determines whether or not to limit the certain request on the basis of loads when processing a request belonging to the specified request pattern.
In the case of constructing the above-described server in the aforementioned example, it is not only necessary to secure high security in the server, but also reduce risk of a threat (an unauthorized program) from a malicious communication destination via the communication network. For example, Patent Literature 3 discloses a vulnerability diagnosis conducting apparatus capable of diagnosing vulnerability of a host device.
In the case of performing a process for diagnosing vulnerability of the host device, the vulnerability diagnosis conducting apparatus has history information indicating a time at which the process has been performed. In the case of diagnosing vulnerability of a certain host device, the vulnerability diagnosis conducting apparatus estimates a time required for diagnosing vulnerability of the certain host device on the basis of the history information and generates a schedule for diagnosing the certain host device on the basis of the estimated time.